The pathogenesis of vascular catheter infections
- VernacularTitle:血管内插管的感染病因
- Author:
Robert J.SHERERTZ
- Publication Type:Journal Article
- From:
Chinese Journal of Clinical Nutrition
2001;9(2):93-
- CountryChina
- Language:Chinese
-
Abstract:
Biofilms are the source of vascular catheter infections and arefound uniformly on central venous catheters after 3 days.Only about half of these biofilms are culture positive.Of those that are culture positive the timing of initial colonization varies by catheter site:subcutaneous segment (average:5.1 days),tip segment (8.6d),and lumen (13.1d).The more organisms that come to reside on a catheter,the greater the likelihood that the catheter will have associated purulence or bloodstream infection.The risk of catheter-related bloodstream infection ranges considerably from≤2/1 000 patient days (peripheral venous catheters,peripherally inserted central catheters (PICC)),cuffed central venous catheters,ports,10/1 000 patient days (arterial and Wwan-Ganz catheters)to 30-50/1 000 patient days (multilumen,hemodialysis).Intrinsic factors that affect the risk of vascular catheter infection include host factors,type of organism,catheter material,and the manufacturing process.Humans are quite susceptible to Saureus,rabbits are not.S.epidermidis requires a polysaccharide adhesin to produce catheter infections.Silicone catheters have a greater risk of infection than polyurethane,polyvinylchloride,or teflon,and this increased risk is related to excess complement activation.Extrinsic factors that can affect the risk of infection include the use of maximal sterile barriers,chlorhexidine skin preparation,insertion by inadequately trained personnel,the number of line breaks,hyperalimentation fluid (favors yeasts),5% dextrose (favors gram-negative organisms),and lipid emulsions (favors Malassezia).
